Most of us would get black circles around the eyes, we know that it is due to eyes getting tired.
Cut cucumber into thin round pieces. Close your eyes and place them on the cucumber pieces on top of your eyes for 10 to 15 mins.
Then wet a cotton ball with rose water and softly press it around your eyes.
This will keep your eyes cool and will help in relaxing.
You can do this once in 15 days even if you don't have dark circles, but for relaxing your eyes.
(I remember in those days in movies, heroines will have a make-up of dark circles around their eyes to show their sick

; So earlier I used to get scared when I get black circels around my eyes!)